Saving time and money doing maxi/midi preps

Here is a trick. It is very simple, only a bit messy. But it will save you one centrifugation step and 30 minutes. You have to pellet your overnight culture as usual, ressuspend it, lysate it and stop the lysis. So far, as recommended in the protocol. The next step is normally a centrifugation to […]

Buccal cell DNA preps

Important: Extract the DNA within one week of receiving samples. Samples that have been processed should be frozen to prevent degradation. Freeze samples between use each day 1. Add 600 ul of 50 mM NaOH to a 1.5 ml eppendorf tube and insert brush in tube. (Clip off handle of brush with wire cutters so […]

DNA gel extraction trick

To cut the band in an agarose gel for dna extraccion, you need to visualize it first under UV light. And maybe you want to take a picture too. Only a few seconds of UV light can damage and create new undesirable mutations in your dna. To avoid that and still have the picture of […]

Methylation sites

Are you wondering why this enzime you are using doesn’t cut your plasmid? It happened to me! I was doing some easy cloning and there was no way I could get my plasmid cut. I tried several times, I bought a new restriction enzime… until I realized that my enzime was methylation sensitive. What’s that? […]

Good primer design tips

1. Primers should be 17-24 bases in length 2. Base composition should be 45-65% (G+C) 3. Primers should end (3′) in a G or C, or CG or GC: this prevents “breathing” of ends and increases efficiency of priming 4. Tms between 55-75ºC are preferred 5. Primer self-complementarity (ability to form 2º structures such as […]